Gallium: Add format PIPE_FORMAT_R8_SRGB

This format is needed to support EXT_texture_sRGB_R8. THe patch adds a new
format enum, the format entries in Gallium and and svga, the mapping between
sRGB and linear formats, and tests.

  v2: - add mapping to linear format for PIPE_FORMATR_R8_SRGB
  v3: - Add texture format to svga format table since otherwise building
        mesa will fail when this driver is enabled. It was not tested
        whether the extension actually works.
  v4: - svga: remove the SVGA specific format definitions and table entries
        and only add correct the location of PIPE_FORMAT_R8_SRGB in the
        format_conversion_table (Ilia Mirkin)
      - Split patch (1/2) to separate Gallium part and mesa/st part.
        (Roland Scheidegger)
      - Trim the commit message to only contain the relevant parts from the
        split.
  v5: - svga: correct location of PIPE_FORMAT_SRGB_R8 (Ilia Mirkin)

Signed-off-by: Gert Wollny <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Reviewed-by: Ilia Mirkin <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/gallium/include/pipe/p_format.h b/src/gallium/include/pipe/p_format.h
index 57399800fa4..6fb91222f2b 100644
--- a/src/gallium/include/pipe/p_format.h
+++ b/src/gallium/include/pipe/p_format.h
@@ -396,6 +396,8 @@ enum pipe_format {
    PIPE_FORMAT_X1B5G5R5_UNORM          = 310,
    PIPE_FORMAT_A4B4G4R4_UNORM          = 311,
 
+   PIPE_FORMAT_R8_SRGB                 = 312,
+
    PIPE_FORMAT_COUNT
 };